By Vesanto Melina
Many of us wonder whether microwave ovens are sending us to the cancer ward or creating weird molecules in food that our bodies can`t handle. Most Canadian homes have microwaves; obviously they have wide appeal. But what do we know of the health implications of their use? How does microwaving affect nutrients in food?
This cooking method originated when engineer-inventor Percy Spencer was building radars in the 1940s and found that microwaves melted the candy bar in his pocket. Seven years later the first “radarange” (7 feet tall, 700 pounds) was used at a Boston restaurant. The name was changed to “microwave oven” and a small unit was introduced for home use in 1967. In that era, women were entering the workforce and time-saving kitchen devices were welcome.
Microwaves are produced when a magnetron tube converts an electric current to electromagnetic (EM) radiation, similar to radio or light waves. When this interacts with food molecules, heat is generated and food is cooked, starting from the inside. Microwaves can travel through glass, but are reflected from metals, thus doors have a metal screen. Microwave ovens have a better cooking efficiency (57%) than electric convection (17%) or gas convection (9%) ovens. Conventional cooking heats food from the outside by convection (baking), radiation (broiling), or conduction (frying) and the heat gradually travels inward.
- It may surprise you that microwave ovens cause less nutrient destruction than the more lengthy heating processes involved in baking, boiling, or steaming. All cooking involves loss of vitamins and protective phytochemicals, yet among your options, microwaving can result in minimal losses.
- When food is boiled, nutrients are leached into the water that often is discarded. Thus boiling peas or carrots can strip more nutrients than microwaving. Protein is not damaged unless there is overcooking (e.g creating a rubbery egg) and that can happen with any form of heating. Microwave food the minimum time, with little or no cooking water.
· Compared with toasting, baking, barbequing, and frying, microwave cooking produces fewer carcinogens such as nitrosamines or the AGEs (Advanced Glycation End products) that give the desired browning but are toxic.
· Microwaves can result in people with limited skills or time for food preparation getting some nutritious meals and less junk food.
- Early microwave ovens leaked excessive EM radiation. Today’s versions prevent leakage and result in less exposure than people get from cell phones. Yet we absorb EM radiation from power lines, cell phones, airplane flights, computers, fridges, and more. I once had my home checked for EM radiation and the major hot spots were the other side of the wall the fridge backed onto, and an old electric clock. Norbert Hankin of the Environmental Protection Agency says “The real question remains whether there could be cumulative effects.”
- With time, seals on microwave doors can lose effectiveness. Exposure to radiation is highest within two inches of the microwave. Do not stand nearby, watching the item rotate while your beverage or peas heat. Place the microwave out of high traffic areas.
- Many plastics, when heated, release toxic and hormone-disrupting compounds into the food. Don’t microwave (or heat by other methods) food in plastic or styrofoam.
To go without a microwave, some reasonable choices are to heat water in an electric tea kettle and use a toaster oven. Leftovers need not always be reheated, often they taste fine cold. For maximum nutrition, choose a raw or high-raw diet!
Vesanto Melina is a local Registered Dietitian and co-author of bestselling nutrition books including Becoming Raw. Her phone is 604-882-6782; email email@example.com;
web: www.nutrispeak.com, www,facebook.com/Nutrispeak